Method of making bottom rods for railway car brakes



May 22, 1934, K. M. HAMILTON METHOD OF MAKING BOTTOM RODS FOR RAILWAY CAR BRAKES Filed April 14, 1930 INVENTOR ATTOR N EYS Patented May 22, 1934 UNITED STATES METHOD OF MAKING BOTTOM RODS FOR RAILWAY CAR BRAKES Karl M. Hamilton, Chicago, 111.

Application April 14, 1930, Serial No. 444,035

6 Claims.

This invention relates to cast bottom rods for railway car brakes, and more particularly to improvements in their structure and in the method of their manufacture.

The present forms of bottom rod suifer constant and destructive wear about the brake-pin holes, not so much in actual application and release of the brakes as in the constant vibration when in free suspension during the road operation of the car, largely due to the weight of the rod.

An object of the present invention is to provide a bottom rod of great strength and which is light in weight, to decrease the wear about the brake-pin holes.

Another object is to provide such a rod with a body portion hollow in cross section, and which is provided with relatively large bearing surfaces for engagement with the brake-pins.

A further object is to provide a method of making a bottom rod which is inexpensive to manufacture and which can be manufactured easily and quickly.

Another object is to provide a method of making a bottom rod of cast steel by a simple and inexpensive casting and shaping operation.

A further object is to provide a botton rod by a rapid method of manufacture and meeting A. R. A. specifications of strength, form and dimensions.

In the drawing which forms a part of this specification, I

Figure 1 is a side elevational view of a bottom rod installed.

Fig. 2 is a plan view of a bottom rod in finished form.

Fig. 3 is a plan view of a bottom rod as cast.

Fig. 4 is an enlarged detailed plan view of the end of the rod shown in Fig. 3.

Fig. 5 is a side elevation of a portion of the rod shown in Fig. 4 with a section cut away showing the first web structure.

Fig. 6 is a sectional View of the column portion of a rod as cast, taken on line 6-6 of Fig. 3 looking in the direction of the arrows.

Fig. 7 is a sectional view taken on line 7-7 of Fig. 2.

Fig. 8 shows a modified form of the web structure in the column portion of the bottom rod.

Fig. 9 is a sectional view taken on line 9-9 of Fig. 8.

Fig. 10 is a sectional view taken on line 1010 of Fig. 5.

Fig. 11 is a sectional view of a further modification of the structure of the body portion of the rod.

In the preferred embodiment of the present invention, the cast bottom rod 1 is made pref- .erably of electric furnace steel which conforms 'to the specification of the American Railway Association. The rod 1 embodies bifurcated end portions 2 which are alike in shape and structure, and of dimensions and form suitable for use with standard brake mechanism. The end portions are connected by a body or column portion 3, containing a plurality of spaced reinforcing web members 4 integral therewith.

The bottom rod 1 is secured in place in the customary manner between the supporting mem bers 5 of the brake gear, by brake-pins 6 fitting into aligned brake-pin holes 7 formed in the bifurcated end portions 2 of the bottom rod 1 and which are secured against lateral displacement by any suitable means such as cotter pins and protective washers. V

The brake-pin holes '7 in the end portions 2 of the bottom rods 1 are strengthened and given a wide bearing surface by the bosses 8 from which may extend a reinforcing rib 1% along each side of the hollow intermediate portions of the rod.

In order to secure a relatively light, strong body portion 3 of the bottom rod, this portion is cast substantially U-shaped in cross section, and is provided with a plurality of laterally extending integral reinforcing webs 4. In accordance with the specifications of the American Railway Association, the castings are allowed to cool and are then uniformly heated to the proper temperature to refine the grain and allowed to cool uniformly.

The sides 9 of the U-shaped portion extend upwardly a substantial distance above the reinforcing web members and are spaced apart, as shown in Fig. 3, when the rod is cast. The upstanding sides 9 may then be readily shaped by a shaping operation to form a closed section, as shown in Figs. 2 and '7. This section may be any desired shape, but is substantially oval or circular, and forms a very strong and rigid body portion which will withstand considerable force under compression.

The integral reinforcing webs 4 are provided so that the upper portions of the upstanding sides 9 may be readily shaped without causing a bending or distortion of the lower portions of the sides, and thus a very strong rigid body portion of substantially circular shape and uniform strength to resist longitudinal compression is provided. Deformation of the ends of the body portion of the rod during the shaping operation is prevented by the laterally disposed reinforcing rib member 17.

Since the bottom rod is initially cast, the reinforcing webs may be very easily formed in the mold and formed of the desired shape to strengthen the sides 9 so that the upper portion may be readily shaped to form a substantially symmetrical body portion of the desired'shape; It is preferably to have the rod substantially oval or circular in cross section, and for this purpose the extend from one side wall, sloping downwardly to a point near the base of the opposite side.

When reinforcing webs of this type are used, some may extend from each side wall to the bottom of the opposite side, and these webs may, if desired, be alternately spaced as shown in'Fig. 8, so that the side walls of the body portion of the rod may be pressed together to form a sub stantially tubular body portion.

Preferably the side walls 9 of the rod are so cast that when they are pressed together they will close the body portion of the rod substantially throughoutitslength, as shown in Figs. 2 and 7, and, if desired, the abutting edge portions of the side walls 9 may be welded together.

A further modification of the body portion of the rod is shown in Fig. 11. In this figure a pair of side walls 15 is disposed in opposed relation with an integral spacing web 16, which may be continuous or interrupted, extending between the side walls to permit the shaping of the edge portions of the side walls 15 to form a substantially tubular body portion, as shown in dotted outline.

I By making the bottom rod initially as a' casting, green sand cores may be used in the U-shaped or body portion, which, of course, lessens the cost of manufacture. Also the intermediate portions of the rod between the bifurcated end portions and the body portion may be cored out to lighten them, and they are preferably reinforced by the ribs 14 which may merge into the bosses 8, thus making the several bosses for each member of the bifurcated end portions and the adjacent rib l4 integral. Such coring maybe done as indicated in Figs. 4 and 5, so that the openings 12 and 13 are formed between the body and bifurcated ends, which facilitates the placing of the cores.

It will thus be seen that bottom rods manufactured according to my invention can be readily cast and shaped to produce a relatively strong, light rod, and which can be manufactured at relatively lowcost',

It will also be seen that by shaping the body portion of the rod to a tubular form the total height of the side walls of the rod is lessened, which is advantageous in the application of the rods to the brakes of standard design.

It will also be seen that by making the rod of cast steel it is much more resistant to corrosion and action of the elements than rods made of more corrosive metal such as is necessary for forgings and the like, and less metal may be used to form a rod of sufficient strength to meet the specifications required.

The design of the rod is such that it lends itself to casting a multiplicity of rods in the same mold, and after casting the rods may be readily shaped by a single pressing operation to close the body portion to form the body portion of substantially tubular shape.

Furthermore, it is to be understood that the particular forms of apparatus shown and described, and the particular procedure set forth, are presented for purposes of explanation and illustration, and that various modifications of said apparatus and procedure can be made without departing from my invention, as defined in the appended claims.

What Iclaim is:

1. The method of making a bottomrod, which comprises casting the rod with a body portion having'spaced sides and reinforcing means extending part way up the sides from steel which iscapable of being shaped, and shaping the upper portions of the sides to form a closed tubular body portion.

2. The method of making a bottom rod for brake mechanism, which comprises casting the rod with bifurcated end portions and with a body portion having reinforcing means integral therewith from steel which is capable of being shaped, the reinforcing means serving to permit shaping of the upper portion of the side walls withoutdistortion of the lower portion of the side walls, and bending the upper portion of the side walls to form a substantially closed tubular body portion.

3. The method of making bottom rods for railway brake mechanism, which comprises casting a rod with suitable end portions, and a central body portion having upstanding side walls and integral reinforcing means in the bodyportion to resist movement inwardly of the lower portions of the side walls thereof from steel which is capable of being shaped, and bending the upper portions of the side walls of the body portion to form a substantially closed tubular body portion.

4. The methd of making a bottom rod for brake mechanism, which comprises casting the rod with bifurcated end portions and with a body portion having side walls and reinforcingmeans integral therewith from steel which is capable of being shaped, thereby permitting the shaping of the edge portions of the side walls to form a substantially closed tubular body portion.

5. The method of making bottom rods for railway brake mechanism, which comprises casting the rod with bifurcated end portions and a central body portion having a lower portion and upstanding side walls and with a plurality of ribs integral with the lower portion of said central body portion and terminating substantially midway of said upstanding side walls, said rod being cast from steel which may be shaped, and pressing the upper portions of said upstanding side walls unsupported by said ribs toward each other to substantially close said body portion, thereby forming a substantially tubular structure.

6. The method of making an integral cast steel bottom rod for railway brake mechanism having a hollow body portion, bifurcated end portions and hollow throat portions connecting the body portions and the end portions, which comprises casting steel which may be shaped about a core extending throughout the length of the rod and having transverse grooves in the body portion thereof to form a casting having upstanding side walls, integral transverse ribs in the body portion thereof, throat connecting portions and bifurcated end portions, and pressing the upper portions of the side walls of. the body portion of the casting toward each other whereby a cast steel brake rod is formed having a substantially tubular, reinforced body portion with integral end portions connected therewith by hollow throat portions.

KARL HAMILTON. 

